Disintegrator having means for recirculating fluid currents from the material discharge hopper to the disintegrator chamber



A. 2, 1949. c. w. LANTER DISINTEGRATOR HAVING MEANS FOR RECIRCULATING FLUID CURRENTS FROM THE MATERIAL DISCHARGE HOPPER TO THE DISINTEGRATOR CHAMBER Filed Sept. 17, 1943 3 Sheets-Sheet 1 dlaz/ ezzzoifi' Clarerzce lfZarzzer Aug. 2, 1949. LANTER 2,477,627

DISINTEGRATOR HAVING MEANS F0 RECIRCULATING FLUID CURRENTS FROM- THE MATE IAL DISCHARGE HOPPER TO THE DISINTEGRATOR CHAMBER Filed Sept. 17, 1943 5 Sheets-Sheet 2 W Wm : umunmmm l x.: s

j ifor/m Aug. 2, 1949. c. w. LANTER DISINTEGRATOR HAVING MEANS FOR HECIRCULATING FLUID CURRENTS FROM THE MATERIAL DISCHARGE HOPPER TO THE DISINTEGRATOR CHAMBER 3 Sheets-Sheet 3 Filed Sept. 17, 1943 r e 7 M f material may be admitted to the hopper.

Patented Aug. 2, 1949 UNITED STATES PATENT OFFICE THE MATERIAL DISCHARGE HOPPER TO THE DISKNTEGRATOR CHAMBER Clarence W. Lanter, Bartlett, I1l.-, assignor to Birtman Electric Company, a corporation of Illinois Application September 17, 1%)43, Serial No. 502,755

4 Claims.

This invention relates to a disintegrator or hammer mill and more particularly to a mill which is adapted for home use.

Disintegrators of the hammer mill type have heretofore been unsuited for domestic use because of their size, noise, and particularly because of the amount of dust produced thereby. Attempts have been made to provide dust filters but these rapidly become clogged and it was characteristic that dust from the disintegrator sifted into the surrounding area.

The present invention is a disintegrator which is compact and yet is completely self-contained without a current of air into or out of the mill. In the preferred form of the structure no filters are required, the device providing an internal circulation of air which ultimately permits the dust produced by the disintegrator to settle.

The invention is illustrated in the drawings in which Fig. 1 is a front elevation partly broken away; Fig. 2 is a sectional elevation taken along the line 22 in Fig. 1; Fig. 3 is an enlarged view of a rotor, viewed from the side; and Fig. 4 is a view corresponding to Fig. 1 with the rotor removed.

The disintegrator comprises a metal housing l made up of a base H and a top l2. The base is provided with an inwardly flaring flange l3 providing a shoulder is upon which the lower edge E5 of the top rests. A gasket 16 of any suitable type may be provided within the flange in order to produce a satisfactory seal.

The back wall of the housing is provided with a circular opening ll adapted tightly to enclose a motor E8. The front wall of the housing is provided with a larger opening 59 provided with a closure 20. The closure 20 may be held in place in any suitable manner such as by two or more handles 21 alfixed to the front of the housing.

Internally the housing is divided into four main compartments as shown in Fig. 2. These comprise the bin 22 which occupies all of the base I l and a portion 23 of the top formed by the rear wall 24, by the hopper walls 29 and 30 surrounding the motor 88, and partly by the vertical wall 26. The wall 25 also forms the rear wall for the disintegrator compartment 21. The disintegrator compartment is in the front of the disintegrator. The third compartment in the machine is the hopper compartment 28, best shown in Fig. 1 and bounded by the sloping hopper walls 29 and 30, and the upper outer wall of the top l2. An opening 3| with a cover 32 is provided in the extreme top of the housing through which grain or other The fourth and last compartment is the motor compartment 35 which is bounded by the solid annulus 3B surrounding the motor, by the front face 31, and by the rear face 38 of the motor. The motor itself projects at the rear from the housing, and at the front the shaft 39 of the motor projects into the disintegrator chamber and serves as a mounting for the disintegrator 40.

It will be observed that there is no opening to the outside from the bin or from the disintegrator chamber which remains open during operation of the device. The hopper opens to the outside only through the cover opening 3|. The motor is closed from the hopper, from the bin, and from the disintegrator chamber.

The hopper is provided with a vent 5B in the vertical wall 26 which forms the back of the disintegrator chamber. The size of this opening is controllable in any suitable way. As shown, it is controlled by means of a movable face plate 5i mounted on the wall 26 around the face 37 of the motor. The plate '51 is constructed so that when it is in the position shown in Fig. 1 the hopper vent '50 is completely closed, but when it is rotated, the opening is progressively opened. The plate 5| may be rotated by manipulation of the handle 52 at the top rear of the housing, as shown in Fig. '2. This handle is secured to a shaft 53 extending through the hopper chamber and the wall 26. At its forward end is a crank arm 54-, the crank of which is provided with a lug 55 extending into a slot 56 in the plate 5!. Rotation of the crank arm in a clockwise direction, as shown in Fig. 1, progressively opens the opening Sil, and conversely, movement of it in the opposite direction progressively closes the hopper vent and per-- mits grain to flow at a desired rate into the disintegrator chamber.

The disintegrator chamber is provided, in addition to the disintegrator 30, with a removable screen 60 which extends approximately threequarters of the way around the housing. This screen may be held in :place in any suitable manner and is shown as set into an annular groove 6! in the wall 26 in which it is held in place by the cover 20-. The screen may be removed manually after removal of the cover and replaced by another screen, or in some cases the screen may be omitted entirely. That portion of the circumference of the disintegrator chamber not enclosed by the screen is provided with a fixed crusher bar 62 as shown in Fig. 1. Both the screen and the crusher bar extend entirely across the periphery of the disintegrator chamber.

The screen provides communication between the disintegrator chamber 21 and the bin 22, this communication being complete throughout the length of the screen.

A second means of communication between the bin and disintegrator chamber is provided by a group of openings in the wall 26. The wall 26 covers the entire rear face of the disintegrator chamber except for the necessary motor, vent, and crank openings, and in addition is extended outwardly therefrom to the outer housing walls in the housing top. As a result, the Wall 26 forms a bafile roughly in the shape of two horns, as shown in Fig. 1, between the upper front part of the bin and the upper rear part thereof. During operation of the disintegrator, the rotor produces a current of air through the screen which tends to build up the pressure within the bin. This pressure is relieved, back of the bafiieformed by the wall 26, through the openings 10 which admit air to the disintegrator chamber on the vacuum side of the air current produced by the rotor.

It will be observed that except for the vent opening 50 there is no connection directly or indirectly between the outer air and either the disintegrator chamber or the bin. Furthermore when constructed as shown, no noticeable draft is produced between the hopper and the disintegrator or the bin through the vent 53. All of the circulation of the air which occurs is in a cycle from the disintegrator chamber to the bin and back again to the disintegrator chamber.

The motor [8 is directly connected, as shown, to the disintegrator 40. For this reason the motor should be a high speed device. The drawings shown are made to scale with the disintegrator arm substantally 9% outside diameter. For this structure a motor of about 0.4 horse power and having a full speed of approximately 8,000 R. P. M. is preferred. Such a motor under light load will run from 6,500 to 1,000 R. P. M. The speed of the motor may be controlled by electrical means or by control of the feed of grain to it. That is, a wide opening of the gate 50 will produce coarser grinding due partially to the slowing down of the motor.

It is important that the temperature of the material being ground be kept as low as possible. The present device produces ground grain showing practically no increase in temperature. In order to accomplish this it is desired that as much cooling as possible be provided. It is, therefore, desirable that the motor be provided in the usual manner with a fan 80 and that its housing be so vented to the air as to draw a current of air through the fan into and out of the motor.

In addition the housing is all made of metal, in order that heat transmitted to any part of it by contact with the grain or with the motor be conducted to the outside and transmitted to the atmosphere.

The rotor or disintegrator or hammer, as it is variously called, is preferably constructed in the manner shown in the present drawings.

Disintegrator arms have heretofore depended largely upon a hammering action in which material to be ground is fed to variously distributed hammers and crushing blocks under extreme conditions of turbulence. The result of disintegration of that type naturally depends upon pure chance. Great turbulence obviously requires an excessive amount of power, and since the power is converted to heat, the heat generated is large.

In the present device it is desired to hold heat to a minimum. Furthermore, the more uniform the grinding, the less is the proportion of powder produced. It is, therefore, desired to produce a flow which is substantially an air flow with the zone of turbulence greatly reduced and confined substantially to the area between the tip of the disintegrator and the screen.

The usual hammer or disintegrator consists of a series of arms arranged in groups, successive groups overlapping openings in the preceding group. In the present form a single disc shaped rotor is employed having at least three and preferably four faces extending at substantially right angles to the disc as shown in Fig. 3. Each arm 4! is progressively cut away to provide a series of hammer arms 42, 43, 44 and 45, thereby increasing the number of sharp corners available for contact with the grain. Each of the arms 4! occupies exactly the same position relative to the axis of rotation and also occupies substantially the entire horizontal dimension of the disintegrator chamber. The vertical dimension of the arm 41 is quite small, that shown being approximately Rotation is so rapid that grain falling from the vent 50 does not acquire a velocity sufficient to drop past the arms 4|. In fact in the apparatus as shown, the grain is always struck by the upper edge of an arm 4| as its first impact. The distance between the arms 4i and the screen 60 is likewise kept small. As a result, the grain being ground is confined almost entirely to the annulus formed by the rotating inner side of the arms 4! and the screen. By maintaining all of the material in this narrow Zone, the opportunity for selective action by the air upon the powder is increased so that the velocity of the air stream may be kept low, and at the same time more selective.

The size of the openings in the screen 60 is based upon the degree of fineness to which the material is to be ground. Nevertheless, it is understood of course that practically no material is carried through the screen except by air currents until the close of the operation. The angle of the openings is such that material driven by the arms 4! does not generally penetrate the openings but is driven back into the mass of grain and to the striking arms.

In operation of the device the hopper is filled to the desired extent through the opening 3|. Thereafter the motor is started and after it has gotten up to speed, the gate 50 is opened by rotating the handle 52. In some cases it is desirable to interconnect the motor switch with the handle 52 in such a manner that the gate 50 cannot be opened until the motor is running. The material to be ground, which may be Wheat, corn, barley, oats or other grain, or any other suitable material for grinding, for example, such as soy beans, drops from the gate 50 into the disintegrator chamber, and, as already pointed out, is struck by an arm 4! during its fall. This fractures the grain and the pieces are thrown against the screen 60 from which they rebound and are again struck by an arm 4!. When a sufflcient degree of fineness has been established, the air currents created by the rotor carry the particles through the screen 60 into the bin 22. The outward motion of the air through the screen creates a slight suction on the inside of the arms 4| and this suction is relieved by the passage of air through the openings 10 from the bin 22 or around the arms. The amount of air so circulating is relatively small and as a result the powder or flour settles almost entirely within the bin amass? and the air which is redrawn into the disintegrator or chamber is relatively pure. It is not necessary that it be completely free from dust because it eventually returns to the bin. However, it is desirable that the dust settle as much as possible because any dust recirculated is subject to an additional disintegrating operation which is unnecessary.

It is perhaps surprising that no substantial draft is noticeable in the hopper chamber even though the lid be left off.

After the grinding has been completed, the motor is turned off and the top I2 is lifted from the bottom H.

The foregoing detailed description has been given for clearness of understanding only, and no unnecessary limitations should be understood therefrom.

What I claim as new, and desire to secure by Letters Patent, is:

1. A disintegrator housing including a hopper chamber, a rotor chamber, a motor mounted in a motor chamber extending through but sealed from the hopper chamber with the outer ends of the motor chamber projecting beyond the hopper chamber, said motor including a shaft which extends into the rotor chamber, a disintegrator mounted on the shaft and having disintegrator arms at its periphery, an opening from the hopper chamber into the rotor chamber at a point below the motor and closely adjacent the disintegrator arms and the bottom of the rotor chamber, and means for removing disintegrated material from the rotor chamber, said hopper chamber being disposed about the longitudinal periphery of the motor chamber.

2. A disintegrator comprising a substantially air-tight disintegrator housing including a disintegrator chamber, a feed chamber also airtight and including a feed opening to the disintegrator chamber near the bottom thereof, a disintegrator rotor including disintegrator arms, means for rotating it at high speed, the disintegrator rotor being shaped to produce an outward current of air when so rotated, a circular screen adjacent the disintegrator rotor, a flour chamber beyond the screen, and means for returning air from the flour chamber directly to the disintegrator chamber at a point on the vacuum side of the disintegrator arms, said feed opening being just above and closely adjacent the rotating arms.

3. In a disintegrating mill, a rotor, a rotor chamber, means for rapidly rotating the rotor, a blade on the rotor for disintegrating material, said rotor being shaped to produce a radially outgoing current of air, an opening for feeding material to the rotor chamber on the vacuum side of the rotor with the bottom of the opening being just above the zone of rotation of said blade, a collecting bin communicating with the rotor chamber into which the air carries finely disintegrated material, and a separate air passageway from the bin to the rotor chamber opening into the rotor chamber at a point on the vacuum side of the rotor, said rotor chamber, collecting bin and air passageway being self-contained to constitute a closed air-tight system,

4. In a disintegrating mill, a rotor, a rotor chamber, means for rapidly rotating the rotor, a blade on the rotor for disintegrating material, said rotor being shaped to produce a radially outgoing current of air, a feed chamber, a gravity feed opening between the feed chamber and the rotor chamber on the vacuum side of the rotor with the bottom of the opening being just above the zone of rotation of said blade, and a collecting bin communicating with the rotor chamber into which the air carries finely disintegrated material, said feed chamber, gravity feed opening and rotor chamber being self-contained to constitute a closed air-tight system.

CLARENCE W. LANTER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 43,374 Witmer June 30, 1864 204,849 Sherwin June 11, 1878 994,596 Marks June 6, 1911 1,213,149 Bodey Jan. 2 3, 1917 1,305,413 Schutz June 3, 1919 1,646,720 Andrews Oct. 25, 1927 1,773,228 Jungels Aug. 19, 1930 2,045,211 Whitfield June 23, 1936 2,052,311 Lindgren Aug. 25, 1936 2,308,578 White Jan. 19, 1943 2,365,179 Egedal Dec. 19, 1944 FOREIGN PATENTS Number Country Date 8,054 Great Britain (1887) Mar. 29, 1888 526,314 France June 29, 1921 649,150 France Aug. 21, 1928 687,872 France May 5, 1930 705,451 France Mar. 9, 1931 5,106 Germany May 21, 1879 20,279 Germany Nov. 30, 1882 340,732 Germany Sept. 17, 1921 344,342 Germany Nov. 19, 1921 

